Vapor electric device



Oct. 19, 1948. M. GARBUNY ET AL VAPOR ELECTRIC DEVICE Filed Oct. 23,1947 WITNESSES:

INVENTORS Max fiarbuny ana/ Ea&er/ 5 ATTORN EY fatented Oct. 19, 1948Max Garbuny and Robert E. Hull,

Pittsburgh, Pa.,

assignors to Westinghouse Electric Corporation,

East Pittsburgh, Pa., a

vania corporation of Pennsyl- Application October 23, 1947, Serial No.781,638

9 Claims.

bration or shock which may be applied through the mountings to theconstruction of the tubes themselves. The vibration may not only affectthe stability .of the cathode materials, but may damage the elementswhich are normally supposed to beunaffected by operation.

For example, the insulating and vacuum-proof seals may be easily crackedby the vibration or shock applied to the vehicle, as by contact of alocomotive witha string of standing cars or the explosion of a mine ortorpedo against the hull of ifi a vessel. Not only are the seals apt tobe damaged, but it has been found that the pendulous mass of some of theelectrodes tends to cause displacement of the elctrodes so that they maycome in contact with each other, portion of the container, 'or evenbecome loosened in their mountings. Y

It has heretofore been proposed to utilize a heavy insulating bushingcomposed of a composition ofmica and lead-borate glass to mount theanode stems in vapor electric devices. However, such'devices have provedinadequate, as 'it has been found substantially impossible to producesuch devices having a desired vacuum tightness. Also, it has beenproposed to utilize glass-metal seals in which relatively thin metalcollars are sealed into the ends of glass cylinders to provide a sealaround the electrode bushings of vapor -electric devices. Such seals aretotally inadequate when shock or vibration is encountered.

'We have discovered that these two types of seals or bushings may beutilized together, to provide a highly satisfactory shocltproof-se'aland bushing. 'A relatively stable and mechanically strong compositionbushing'is utilized to me- J chanically support various of the electrodeelements; while the glass-metal seal is' resiliently mounted within theheavier bushing and protected thereby so that the glass-metal sealingelement maintains the desired vacuum tightness while the compositionbushing maintains the electrodes in a desired and fixed position.

The use of mechanical and vacuum seals in parallel has afurtheradvantage in that the overall length can be greatly reducedbecause oftheor with some 2 removal of mechanical stress from the vacuumproofinsulator.

It is, accordingly, an object of our invention to provide an improvedbushing assembly for a vapor electric device.

It is a furtherobject of our invention to provide a lead-in constructionin which the electrodes are rigidly held in the desired position.

It is a further object of our invention to provide a composite seal andsupporting structure for a vapor electric device.

7 It is a further object of our invention to provide a vapor electricdevice operable under severe conditions of stress or shock.

Other objects and advantages of our invention will be apparent from thefollowing detailed description, taken in conjunction with theaccompanying drawing, in which the figure is a sectional elevation of avapor electric valve embodying our invention. In the exemplaryembodiment of our invention, an envelope is comprised of a substantiallycylindrical element I to whichis applied a suitable cooling jacket 2 andthe ends of which are composed of inserted headers 3 and 4. The bottomheader 3 of the envelope is provided with a cathode cup 5 for containinga liquid vaporizable cathode material 6 such as mercury, while the topheader 4 is provided with an opening 1 through which an anode stem 8extends to support an anode 9 in cooperative relation to the pool-typecathode 6.

The anode stem 8 is supported by means of a combination seal and bushingconnected to the header 4 and to the outermost end of the anode stem 8.Preferably, the mechanically strong bushing'is composed of a pluralityof sections 10 and l I, each section l0 and II having an insulating bodyI? which may conveniently be composed of a composition of mica andglass, which is available at present under the trade-name Micalex.

The insulating bodies [2 are connected to metal ends I 4, l5, l6 and I!which are preferably connected to the mica-glass composition I2 by meansof a hot molding operation and, if necessary, machined to shape aftermolding. The lowermost section M has a metallic terminal 18 whichinterfits with the opening 1 in the header 4 of the envelope and ismechanically attached thereto, preferably by welding.

The outermost end of the outer segment H of the bushing is provided witha metal terminal I l which has an opening 19 therein forming arelatively tight fit'with the exterior end of the anode lead 8 and isconnected thereto, usually by means ably constructed Of graphite andhavingeaworkeing face 20 which is a segmentv of a sphere in order tohave a maximum workingjarea in, the.

smallest diameter of anode 91. lmmediatelyfsun-l,

4' cylinder sealed between them is applied between the header 4 and theelectrode stem 8. The first such seal has one of its collars 30 attachedby welding directly to the header 4, while the inner collar 3| of theseal is welded in vacuum-tight relation. to that portion 320i. the innershield 21 extending upwardly along the: anoderstem 8. The inner shield32 is then welded in vacuum- I tight relation to the intermediate insertIS in 9, prefer '10" the mechanical bushing, and preferably it is cut.011. at; this point so that a firm and satisfactory weld 33 may beaccomplished. The upper portion 3 11s then tack-welded in place. Thesecond section Offthe vacuum seal is made between the rounding the anode9 is an anode shield 2|, the intermediate insert [5 and the anode lead 8itoperating portion 22 of which is preferably comand is a sphericalsection: toi the shape of the anode face2fl.

posed of graphite conform closely to This graphite section 22' isprovided with a rela tively largenumber of relatively. small openings23".so that the" maximum amount of opening in the shield 2| is providedwithout mechanically weakeningthe' shield face 22 more'thanis abs0-l'ut'ely necessary: The anode-shield 24 not only conforms in shape tothe anode 9'; but extends al'ongthe' majfoi portion: of" the anode lead8 and issupportedfintermediate thelength of the bush ing bya'tightmechanical'bearing on one or more of theintermediate inserts l'5'- or"I6";

Preferably; a plurality, for example three,

shields, arev utilized about" the anode 9, the out sideshield 24* beingrelatively close to the en: ve-lop'e and being rigidly supported by aplurality of insulators 25 attachedtoth'e header'd. The

intermediateshields26 -may likewise be supported on the" insulatingbushings 25- by means of flanges 2"! engagedontheinsulators 25. 'All oftlie' sliield's' 24; 24" and 23- are-preferably provided withsubstantially"cylindrical metal portions and spherical sections ofgraphite for-working faces; The inner shield 2 beingconnected directlytoone'of the inter-mediate inserts suchas I5", is provided with aconvenient method' ofapplying potential by simply' connectingthepotenitial lead 28 t'otheinsert I5 Where-more tliantvvo seetions=oftheinsulatingbushing are utilized; one ormor'e-ofthe interior shields26' may be similarly mounted and similarly-'oonnected to any suitablesource ofsuppl-ya The external shield 24 is preferably connect'ed toacontrol' potential by means of'an' insulating bushing 2'9 inser-tedthrough an opening in the header. Obviously, one-or all of the shieldscouldbesimilarly connected.

"A composition-bushing, beoauseof itsmechan-i cal strength andrelativelylarge bearing surfaces; is: capableof supporting the anode 9and the inner shield 21 in rigid. spaced relationship soithati vibrationof' the oont'ainer'is not apt to produce contact; between the; shield 2iand the anode- 9: Eikewise; the rigid mounting to the header and? therelatively short moment arms secured thereby; supports: the intermediateand outershields- 24 and 26 so that'vibrationwill not produce contactbetween the; electrode members.

Where-itds desired to reduce thelengthof the bushingwtb a minimum, theouter-surface of the ihsulatingbodiesa I23. may: beeprovided with ridgesorc grooves: in. arkn'oW-n: manner to increase the surface distancewhile the spacebetween: the supporting bushing and thevacuum sealisfilled with an eleotronegative gasor" a fluid of high electric breakdownstrengthz In order: to\produce=the suitableva'cuum tightness. to. thebushing; inner vacuum-tight" seals oomprisihglasplurality ofimetalcollars and a glass being welded to the electrode lead 8.

The cathode assembly is preferably of the deep-dish variety, the dish 5having a top edge 3 contoured so that inclinationof the tube doesnot'spill'th'e cathodematerial-G out of the oathode cup 5. A pluralityof make-alive electrodes 4'3; one of which is shown; are usuallyprovided for i'nit-iatingtliecathode s'pot; If" desired; keep aliveeleetrodesdd maybe provided' for maintaining the cathodesp 0t for apredetermined inter-' val after its-- initiation. The cathode; dish 5 isusually provided with an enlargement 42 adjacent the normalworkingposition sothat any,

cathode -material which is evaporated to provide the working vapor" ofthe device will not, unduly low-er'tl'le level of the. cathode material6 in the cathode cup5. I

Preferably, the: cathodecup 5 is: substantially filled with wire mesh43- of a fineness suehthat mercury: will slowly flow through it, butwhioh is substantially impervious: to rapidly: moving mercury;Rrefe'rably; acathodeshield 44 is mounted directly 'ab'ove thecathodecup 5 in er-- der toipreventc direct motion: of cathode materialEfrem the-cathode i'nto the-vicinity of the anode 9. andshieldlelectrodes 2J--24--26-i Also; in or derzt'o. prevent mercury:from: travelling upthe sides ofi'theicontainen,.a :.baffiez45iringisprovided intermediate the anode: and. cathode region. While we haveshown the cathode baflie-ME as-=being: mounted. onithe cathode dish inmany instanoes'we have: found; it: desirable: to mount; thecathodelbaffle 4'4 onithez baffle;- ring: 45: so that they form; a.substantially integral: construction.

In; order: to: prevent, vibrationof thev tube it.- self; we;provid'e'armountingzdfii attor. adjacentzthecathodezand:aasecondzmounting. 4]: at .or adjacent the anode level;. setthattthej: envelope.- it'self; isrigidlyxmountedan'dmotisubjectntdvibrationz In: the oonstructione of: a.device: according: to our invention, a. relatively. large number" of;sub:- assemblies aresproduoedzand these eventuallyastsembledto:produce.aacompleteyalve: The cylindrical; portion hofftheenvelope isprovided with a water-jacket; 211 andjm'ounting: means: 46. and. 4 1;while. the intermediate: fi'owr baffle 45 is. inserted intl'ie properpositiomandweldedimplacer. The cathode header is. then completely:assembled with-the; cathode :dish 5 and: itsadjuncts; together with .thevariousileadeininsulators-1 and: supports for: themake-alive electrodes40;; and; if: desired; the :keep alive electrode Ail; and'theentireheader 3- insertedaas admit-land weldedzin place.

- Thesegments;Hlelilzofthebushing as indicated above preferably:beingi'formed of metal inserts and: a: .composition body by-= hotmolding and; if necessary; final? machining to the desired shape. Thevarious -vacuumseal elements, that is: the

glass collars Il5I and the relatively thin metal collars 3ll-3I; 35-36,are constructed and utilized as units. The lower vacuum seal 3| is thenwelded to the tubular portion 32 of the inner shield 2|, which tubularportion 32 is then inserted in the metal intermediate insert I5 of themechanical bushing and preferably fusion-weldedv in place so as toprovide a vacuum-tight connection'33 between the inner shield 2I and theintermediate insert I5, also. a vacuum-tight weld 'between the innershield 2i and the upper collar 3I of the lower vacuum bushing. The lowercollar 30 is then fusion-welded to the edge of the opening I in theheader 4 so that the header 4 and lower sections of both the mechanicaland vacuum bushings are in a unitary piece.

The upper end 34 of the tack-welded in place. If desired, the portion 34can be spun out so that it may be weldedwithout danger of interferingwith the first vacuum-tight weld 33. The upper metal collar 36 of thesecond seal is then welded to the lead-in stem 8 which is then insertedthrough the tubular portion 32 of the inner shield 2| and the lowercollar 35 welded in vacuum-tight relation to the intermediate insert I5.The exterior portion I I of the mechanical bushing is then inserted overthe leadin stem 8 and; the; meeting intermediate sections bolted orotherwise secured together and the exterior insert II welded orotherwise secured to the lead-in stem 8. "In this manner, there is adirect mechanical support for both the inner shield 2| and the lead-instem 8, with its anode 9.

The entire assembly is then inverted and the upper flange 55 of theouter shield 24 is connected to the header 4 and, if desired, to thepotential lead-in 29. The supporting flange 21, the tubular section 56and top section 5'! of the intermediate shield 26 are then put in placeand secured on the insulating bushings 25. The top portion 58 of theinner shield 2| is then attached to and Welded securely to the tubularportion 32 of the shield 2|, after which the anode 9 is attached to theanode stem 8. The cylindrical portion and working face 22 of the innershield are then attached to the upper portion 58 of the shield,preferably b means of screw-threaded fastenings 60 which are thenspot-welded to prevent loosening =by vibration. The intermediate shield26 with its working face is then attached in the same manner and finallythe outer shield 24 is attached to its supporting flange. The entireanode header assembly is then inserted into the tubular portion I of theenvelope and welded in vacuum-tight relation to provide a completelyunitary device which may be evacuated and sealed ofi, if desired.

This construction provides a converter valve, the envelope of which iscompletely rigid, while having the necessary vacuum tightness and havingthe necessary mechanical sup-port for maintaining the internalelectrodes in fixed relation to each other and to the envelope in spiteof excessive vibration or shock.

While, for purposes of illustration, we have shown and described aspecific embodiment of our invention, it will be apparent that changesand modifications can be made therein without departing from the truespirit of our invention or the scope of the appended claims.

We claim as our invention:

1. A shock-resisting construction for a vapor electric valve comprisingan elongated metal envelope, the top end of said envelope including aheader having an opening therein, an anode in inner shield is then.

embedded therein, one of said said envelope, "Said anode having aWorking face shaped as a spherical section, a metallic anode stemattached to said anode and extending through said opening, an insulatingbushing rigidly supporting said anode stem with respect to saidenvelope, an anode shield substantially enclosing said anode andextending along the major portion of the anode stem, means intermediatethe ends rigidly supporting said anode shield, a vacuumproof sealbetween said envelope and said anode shield and a vacuum-proof sealbetween said anode shield and said anode stem.

2. A shock'proof electric valve comprising a metallic envelope, a headerhaving an opening therein, an anode in said envelope, an anode stemattached to said anode and extending through said opening, amechanically strong insulator attached to said envelope and the outerextremity of said anode stem, and a resiliently mounted glass-metalvacuum-tight seal between said envelope and said anode stem.

3. A shockproof electric valve comprising a metallic envelope, a headerhaving an opening therein, an anode in said envelope, an anode stemattached to said anode and extending through said opening, amechanically strong insulator attached to said envelope and the outerextremity of said anode stem, 2. resiliently mounted glass-metalvacuum-tight seal between said envelope and said anodestem, a pluralityof shields about said anode, the inner anode shield extending throughthe major portion of said anode and said anode stem, said inner shieldIbeing mechanically supported intermediate the ends of said insulator.

4. A lead-in assembly for a vapor electric device comprising asubstantially cylindricalenvelope, a header in said envelope having anopening therein, an electrode in said envelope, a rigid supportingconnection for said electrode, said connection extending through saidopening, a bushing including a body portion of a composition of mica andglass with metal end portions end portions being welded to said headerabout said opening, another of said end portions being welded to saidconnection, a shield having a tubular portion enclosing the majorportion of said connection, a vacuum-proof insulating seal between saidheader and said shield and a second vacuumproof insulating seal betweensaid connection and said shield.

5. A lead-in assembly for a vapor electric device comprising asubstantially cylindrical envelope, a header in said envelope having anopen ing therein, an electrode in said envelope, a rigid supportingconnection for said electrode, said connection extending through saidopening, a bushing including a body portion of a composition of mica andglass with metal end portions embedded therein, one of said end portionsbeing welded to said header about said opening, another of said endportions being welded to said connection, a shield having a tubularportion enclosing the major portion of said connection, a vacuum-proofinsulating seal between said header and said shield and a secondvacuum-proof insulating seal between said connection and said shield,and a filling of electronegative gas in the space between the bushingand the vacuum-proof insulating seal.

6. In a vapor electric device having a metallic envelope enclosing aplurality of electrodes, an

ages-1 ,938:

it anode, an. anode stem secured to -said anode; a rigid insulatingbushing secured to'said stem and said-envelope to rigidlysupport saidanode in re lat-ion. to said envelope; an electrode closely surroundingsaid anode and-said anode'stem, means intermediate the ends of saidrigidninsulating bushing for rigidly mounting-sai-d -electrode;:.asecondelectrode closely enclosingisaid first mentionedelectrode, insulatingmeans for rigidly mounting said second electrode on said.envelope.

'7. In a vapor electric device having a metallic envelope enclosing aplurality of electrodes; an anode, an anode stem secured to 'said anode;.a rigid insulating bushing-secured to said stem -and said envelope torigidly, support said' anode in relation to said envelope; an electrodeclosely-. surrounding said/anode a'ndx sa'idxanode stem, meansintermediate the endsof saidi'ri'gid insulatingwbushing for rigidlymounting-asaid 'elec trode;;.a.second electrode closely; enclosing; saidfirst. mentioned electrode, insulating means for rigidly mounting saidsecond electrode on said envelope, and a resilient vacuum-proofinsulating-wseal between said envelope and: said anode stem;

8:v In aivapor electric device having-a metallic envel-ope'enclosing'aplurality'of electrodes; an' anode, an anode stem secured to-said anode,a rigidiinsulating bushing secured to said stem and saidzenvelope torigidly supp-ortisaid anode in.

relation to said envelope, an electrode. closely? sea surrounding: saidanode and said anodezstemfi means intermediate the ends --of said'rig'id ins'i'r-w lating bushing for rigidly mountingsaidaelec trode;asecond electrode closely: enclosihg'ss-aid between saidenvelopeand'said anode stem, and a-filling fluid having a' highelectrical-break 1 down betweentsaid rigid insulating bushing; and

said-'vacuum proof insulating-J seal. 1

9. Ina vapor electricdevice havinga metallic-v envelopeenclosingarplurality of electrodes; an anode, an anode'stemsecuredto said anode;a rigid insulating bushing secured to said stem and said envelope 'to'rigidly supportsaid anode in relation to said envelope, an electrodeclosely surrounding said anode and said anode stem} means intermediatethe ends of said rigid insu lating bushing for rigidly mounting said"elec--- trode, a second electrode closelyi enclosing said firstmentioned electrode, insulating means for rigidly mounting'said'secondelectrode on -saidenvelope; a resilient" vacuum-proof" insulatingseal between said envelope and said anode stem'; and spaced apartmounting means for rigidly supporting said metallic envelope.

MAX GARBUNYJ lEtOl3E1 t'I'-- E. 1

No references cited.

